Traditionally, when snap fits are used to secure two pieces or devices together, two or more snap fits are used, along with some sort of alignment means situated somewhere on the two parts, remote from the snap fits. This is because all prior art snap fits only constrain the movement of the two parts relative to one another in one direction, or two directions at most. That is, the snap fit restricts the relative movement of the two pieces in only the X or Z direction, or at most, in both the X and Z directions, but never in all three possible directions (X, Y, and Z). Because of this, a traditional snap fit can be easily undone simply by moving one or both of the individual pieces in a direction normal to the direction in which the snap fit was actuated. Thus, designers have been forced to employ an additional securing means, such as retainer pins, cams, pivots, hinges, etc. at a location that is remote from the snap fit, or to employ two or more snap fits. Clearly, this creates a number of undesirable design constraints on products. As an example, portable electronic devices, such as two-way radios and telephones, often have removable battery packages for supplying power. In many such configurations, a removable battery package is secured to a host electronic device by a latch system. The latch system ordinarily includes a portion situated on the battery package, and a portion situated on the host device that mate together to secure the battery package to the host device. When a user removes the battery package from the host device for whatever reason, the electrical terminals of the battery package are exposed, and can be inadvertently connected together by a metal object. THIS is not desirable, as shorting the positive and negative terminals of the battery causes rapid heating of the battery and the metal object, and has occasionally led to melting of nearby objects, or even worse, a fire could occur. One means of preventing this has been to provide a cover for the terminals that can be snapped onto the battery package using the same latch system as employed on the host device. Unfortunately, conventional-art latches and snap fits have required an additional securing means, as these snap fits only constrain the relative movement of the two objects in one or two directions. Thus, unless the two objects are somehow constrained from moving in a third direction, even the tightest of snap fits can be easily undone by simply moving the two members in the unconstrained direction. Thus, in order to secure the cover to the battery, an additional constraining means has to be located remotely from the snap fit latch. The astute reader will appreciate that this causes the cover to be larger than necessary, thus increasing the size and cost of the cover, both of which are undesirable.
Thus, a need exists for fasteners of a type as herein described which can be inexpensively manufactured and which may be easily and conveniently released as desired.